Age, Low Immunoglobulin G, and M Serum Levels Predict Infections in People With AQP4 ‐ IgG + NMOSD Treated With Rituximab—A Multicenter Cohort Study From the German Neuromyelitis Optica Study Group ( NEMOS )

Engels, Daniel; Herfurth, Mariella; Havla, Joachim; Schindler, Patrick; Ruprecht, Klemens; Schwake, Carolin; Ringelstein, Marius; Fischer, Katinka; Schubert, Charlotte; Schiffmann, Insa; Hümmert, Martin W.; Giglhuber, Katrin; Jarius, Sven; Vardakas, Ioannis; Grothe, Matthias; Etgen, Thorleif; Warnke, Clemens; Naumann, Jasmin; Hoffmann, Frank; Senel, Makbule; Wildemann, Brigitte; Berthele, Achim; Trebst, Corinna; Häußler, Vivien; Aktas, Orhan; Ayzenberg, Ilya; Bellmann‐Strobl, Judith; Bergh, Florian Then; Kümpfel, Tania (2026): Age, Low Immunoglobulin G, and M Serum Levels Predict Infections in People With AQP4 ‐ IgG + NMOSD Treated With Rituximab—A Multicenter Cohort Study From the German Neuromyelitis Optica Study Group ( NEMOS ). European Journal of Neurology, 33 (2): e70520. ISSN 1351-5101

Abstract

Introduction:
Rituximab is effective and widely used as long-term treatment in aquaporin-4-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+ NMOSD). However, infections remain a significant concern during rituximab treatment.

Methods:
We conducted a retrospective multicenter cohort study within the NMO Study Group (NEMOS) in Germany, analyzing demographic and clinical data from people with AQP4-IgG+ NMOSD receiving rituximab or azathioprine by retrospective chart, and compared infection occurrence and severity. For rituximab-treated patients, we collected laboratory data (blood lymphocytes, B-cell counts, serum IgG, IgM, and IgA levels), assessed risk factors for infections, and determined the probability of infection within a 3-month window before and after the laboratory assessment.

Results:
In 92/170 rituximab and in 12/33 azathioprine treatment episodes, one or more infections were documented. Rituximab and azathioprine showed comparable types and risk of infection (HR = 1.24, 95% CI: 0.68–2.25). Rituximab-treated individuals older than 60 years had a higher risk of infection (HR = 1.62, 95% CI: 1.02–2.57). Hypogammaglobulinemia (IgG < 6.0 g/L: OR = 2.27, 95% CI: 1.15–4.48; IgM < 0.3 g/L: OR = 2.08, 95% CI: 1.05–4.09) predicted infections and the occurrence of both low IgG and IgM serum levels further increased the risk of infection (OR = 2.77, 95% CI: 1.10–6.98) during rituximab treatment. Low IgG and IgA serum levels as well as lymphopenia predicted infection-related hospitalizations.

Conclusion:
Age > 60 years and immunoglobulin serum levels during rituximab treatment may serve as predictors for infection and help to individualize treatment decisions in NMOSD.

• Dokumententyp: Artikel (Klinikum der LMU)
• Organisationseinheit (Fakultäten): 07 Medizin > Institut für Immunologie
• DFG-Fachsystematik der Wissenschaftsbereiche: Lebenswissenschaften
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 491502892